CN102065149A - Method for lowering playing delay of P2P live broadcast system on basis of performance lamination - Google Patents
Method for lowering playing delay of P2P live broadcast system on basis of performance lamination Download PDFInfo
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- CN102065149A CN102065149A CN2011100074942A CN201110007494A CN102065149A CN 102065149 A CN102065149 A CN 102065149A CN 2011100074942 A CN2011100074942 A CN 2011100074942A CN 201110007494 A CN201110007494 A CN 201110007494A CN 102065149 A CN102065149 A CN 102065149A
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Abstract
The invention discloses a method for lowering playing delay of a P2P live broadcast system on the basis of performance lamination, belonging to the technical field of streaming media and distributed systems. The method comprises the following steps of: calculating and grading liveness to a node; constructing an overlay network topology according to a calculation result; taking the node with high liveness as a backbone layer of the whole overlay network; taking the node with lower liveness as a secondary backbone layer of the whole network; taking other nodes as common nodes; and after the overlay network is constructed, adopting different scheduling schemes for different layers, wherein the backbone layer with excellent node performance enjoys the shortest playing delay, the playing delay of the secondary backbone layer is longer than that of the node of the backbone layer, and the rest can be done in the same manner. The method can lower average playing delay of the system and improves user experience.
Description
Technical field
The invention belongs to Streaming Media and distributed system technical field, be specifically related to the method for playout-delay in a kind of P2P of reduction live broadcast system.
Background technology
Nowadays, the P2P Streaming Media has become a kind of popular broadcasting media distribution approach, and many research institutions continue to study in this field, and a lot of companies also pay attention to using and improving this technology very much.QoS problem in the P2P Streaming Media is popular research direction.For the P2P stream media system,, also be a big focus place of P2P stream media system research because the unsteadiness of node and the difference of node capacity make that the QoS problem in the P2P stream media system is more outstanding.Relatively distinct issues have play continuation degree not high, particularly online numerous in; Channel is long switching time, usually more than ten seconds, causes user satisfaction not high; The broadcast of live broadcast system time-delay is long, has compared inferior position with traditional media such as TV.If these several problems can not solve well, will badly influence user's experience.System of the present invention has reduced playout-delay in the P2P live broadcast stream media, has improved the continuation degree of video playback, has promoted user's experience.
Summary of the invention
The object of the present invention is to provide a kind of continuation degree that can improve video playback, playout-delay method in the reduction P2P live broadcast stream media of lifting user experience.
Exist subject matter to have in the P2P Streaming Media at present: long initial play buffer delay (will wait a period of time to play after selecting channel to click broadcast) and absolute playout-delay (comparing a period of time in evening on playing progress rate with source of media) also have the problem (getting stuck) of reading continuously of playing in playing process.It is poor during this period of time to being presented at client node on the screen in streaming media server coding back that playout-delay is defined as data block at native system.
Adopt certain account form that the liveness of node is calculated, then according to result of calculation to the node grading operation of classifying.
Playout-delay method in the reduction P2P live broadcast stream media provided by the invention, at first, node is carried out liveness to be calculated and classification, liveness according to node carries out the operation of overlay network topology constructing to node, the node that liveness is high will be as the backbone layer of whole overlay network, the low slightly node of liveness is as the less important backbone layer of whole network, and other node exists as general node.
After building overlay network, different levels is adopted different scheduling mechanisms, the joint behavior of backbone layer is good, and contribution is big, and the speed of obtaining data is fast, and these nodes are enjoyed minimum playout-delay.And to less important backbone layer, its playout-delay is greater than the node of backbone layer, by that analogy.
Among the present invention, the data buffer zone is divided into two sections according to functional requirement: forward direction buffering (proparea) and back are to buffering (back zone), the forward direction buffering is used to store the data that are about to broadcast that other node sends, the back is used to store the data block of having play to buffering, and the data of back in buffering can be the node service of those playout-delays greater than oneself.
The present invention comes the computing node liveness and according to result of calculation evaluation node level, then, makes up the overlay network topological structure of optimizing in the node after classification according to the performance of performances such as the upstream and downstream bandwidth of node, stability.The affluent resources that made full use of the high-level node in this process improve systematic function, and give the certain award of these high-level nodes (low playout-delay) as incentive measure.Aspects such as the upstream and downstream bandwidth of node, line duration and channel switching frequency are the important references factors of evaluation node grade.The present invention constructs the liveness grade that series of algorithms is used to evaluate node, make up the topological structure of an optimization then according to ranking result and positional information, adopt specific playout-delay to set scheme at last and the buffering area management algorithm reaches the average playout-delay of reduction system, promotes the purpose of user experience.
One, the node liveness calculates
In the P2P live broadcast system, the upstream bandwidth of node and line duration length (stability) are the key factors that influences systematic function, and we are with the main reference index of these two factors as the level of a node of evaluation.The present invention introduces the reference frame as grading of time index and these two parameters of speed index.Time index is to get according to the line duration of node and the total duration calculation of program, has reflected the stability of a node.The stable more fluctuation that system is caused of node is few more, and the cost that system carries out self-control is also more little, and is favourable more to the even running of whole system.If stable node has higher upstream bandwidth, then it is big more to the contribution of system, therefore, also considers the upstream bandwidth factor of node, promptly on average uploads bandwidth, and the present invention is with its called after speed index.Concrete node liveness computing formula is shown below.Wherein aIndex is a node liveness value, and cIndex is this calculating gained liveness index in real time of reaching the standard grade of node, and hIndex went up line computation gained liveness index for node last time, and timeIndex is the time index of node, and speed is the speed index of node.Time index and speed index calculate and get with formula 3,4 and 5 respectively, wherein L is the duration of whole program, and t is the duration that program one is play, and S is the line duration of node, r is a video code rate, and Quantity is that node is always uploaded data volume during watching this program.
By top calculating as can be seen, the present invention not only calculates the time index and the speed index of the node of each session, also will be used as historical record under these data record, this session and historical record respectively account for certain ratio in the time of the liveness of next computing node.So just fully taken into account node and always showed, have stronger can be with reference to property.
Two, the overlay network topology constructing based on the node liveness of location aware
After the liveness of the node of determining, according to liveness result of calculation node to be classified, the node level that liveness is high more is high more.For the ease of management and the operation of ensuing topology constructing, the present invention is a liveness result of calculation according to the performance performance of node, behind the setting threshold values node is divided three classes: high liveness node, middle liveness node and low liveness node.From the computing formula and the interpretation of liveness, obtain as drawing a conclusion: aIndex is better than average level greater than 1 node; The aIndex value that many nodes are arranged is greater than 1.2, and the aIndex value that a big chunk node is also arranged is less than 0.8; The quantity sum of high liveness node and middle liveness node is less than the quantity of low liveness node.Therefore, the present invention adopt following threshold values setting carry out the division of level: aIndex greater than 1.2 for high liveness node, aIndex be middle liveness node between 0.8 to 1.2, aIndex less than 0.8 for hanging down the liveness node.Concrete threshold values setting also can be adjusted according to concrete application scenarios and node bandwidth distribution.After with node-classification, begin to construct the overlay network topology of an optimization.
The present invention specifically is the backbone network that high liveness node is constructed as whole overlay network, is responsible for the latest data that server produces is transported in each autonomy field system of whole overlay network apace and goes.Because high liveness node has the higher bandwidth and stable preferably of uploading, and can be competent at this task well.In a part of neighbor node of node of liveness be high liveness node, can obtain data and distribute from upper layer node at own place layer.The node that the node of low liveness then can be selected a part of middle and high liveness is as neighbor node, and these nodes have mass data, and therefore low liveness node also can have broadcast performance preferably.
Three, set with the proportional playout-delay of liveness
In general P2P live broadcast system, the playout-delay of all nodes is set for identical to increase the overlapping of node buffering area as far as possible, and then promote the availability of data, and promptly there is more node to have the data block of oneself needs, can guarantee obtaining of data better like this.
Adopt the asynchronous play strategy among the present invention, the overlay network of a channel is divided into several synchronous playing districts according to distance and network condition from data source according to autonomous territory.Near from data source, play earlier in the zone that can obtain data block earlier, and playing after a while from data source other node relay of needs far away.At identical or close playout-delay of having of same play area.Can more early obtain data and can more early begin to play by the good node of guaranteed performance like this, the sequencing of broadcast flows to consistent with the propagation of data.
The playout-delay set algorithm in an autonomous territory is specific as follows described.We use the proportional playout-delay set algorithm based on playout-delay.The acquiescence playout-delay in new autonomous territory calculates according to the playout-delay in the autonomous territory of contiguous more close data source.The playout-delay of a node is to determine that by its initial start skew and initial buffer time in our system, the initial buffer time is fixed, so be offset as long as we calculate initial start.The formula that following formula is offset for the silent initial start of calculating autonomous territory, wherein θ is the acquiescence initial start skew of node, f
p(t
0) be contiguous autonomous domain node P
nBroadcast point, α is system's adjustment factor, L
pBe P
nPlayout-delay.
Set accordingly with playout-delay, data buffer zone of the present invention is different with the buffering area of general popular P2P live broadcast stream media system, and we have used different data buffer zone management strategy.General P2P stream media system can not keep the data of having play, and can directly discard.The present invention is two sections with the data buffer zone cutting: proparea and back zone.The proparea is used to deposit the data of playing from being about to of receiving of other node, and the back zone is used for depositing the data that those have been play, and these data can be used for will being higher than for other playout-delay oneself node service.In the present invention, total size of buffering area is fixed, and the big minor matter of the size in proparea and back zone is determined according to the ability of residing position of node and node self.Set the size of the proparea and the back zone of buffering area according to the size of the playout-delay of node.
Description of drawings
The network topology schematic diagram that Fig. 1 forms for the present invention.
Fig. 2 constitutes schematic diagram for the ordinary node buffering area.
Embodiment
A node is at first classified according to the historical liveness information of node after entering system, if the system that enters for the first time then is defaulted as middle liveness node, and liveness is changed to 0.8.Simultaneously whole in line process node all can carry out liveness and calculate according to formula 1,2,3,4,5, classify according to current result of calculation when reach the standard grade next time.After the classification of determining under the node, can combining position information and the node liveness make up overlay network with the physical network topology coupling.The Tracker server is preferentially selected the node in same autonomous territory or the adjacent autonomous territory when the transmission start node is tabulated to the node of newly reaching the standard grade, and node also can be followed this principle when selecting neighbor node.On the other hand, when selecting neighbor node, also will consider the high liveness node of some distant (not being same or adjacent autonomous territory), the connection degree of whole like this overlay network can improve, and the topology division be difficult for to take place, to the frequent adding of node, withdrawed from resistance preferably.Last employing and the proportional playout-delay set algorithm of liveness in the overlay network topology that builds.Initiate node is adopted proportional playout-delay establishing method (details has description in Fig. 2), the lower playout-delay of node setting that liveness is high, the node that liveness is low is provided with higher playout-delay.Like this, the playing progress rate of node meets the distribution path of media data in the whole system, has quickened the distribution speed of data greatly, has reduced the average playout-delay of system.
Because native system has made full use of the bandwidth and the stability of high-performance node, has made up good overlay network topology, the playout-delay of node have been carried out reasonably being provided with, the average playout-delay and the play continuation degree of whole system all are improved.
List of references:
[1]?Dongbo?Huang,?Jin?Zhao,?Xin?Wang.“Trading?Bandwidth?for?Playback?Lag:?Can?Active?Peers?Help?“ ACM?Multimedia?2010,?Short?paper，October,?2010。
Claims (6)
1. method based on the reduction P2P live broadcast system playout-delay of performance layering is characterized in that concrete steps are:
Liveness to node calculates, and according to result of calculation node is classified to grade then and operates;
To node carry out that liveness calculates and classification after, liveness according to node, node is carried out the operation of overlay network topology constructing, the high node of liveness is as the backbone layer of whole overlay network, the low slightly node of liveness is as the less important backbone layer of whole network, and other node exists as general node;
After building overlay network, different levels is adopted different scheduling mechanisms, to the node of backbone layer, enjoy minimum playout-delay, to less important backbone layer node, its playout-delay is greater than the node of backbone layer, by that analogy.
2. the method for claim 1 is characterized in that node liveness computing formula is as shown in the formula shown in (1); Wherein aIndex is a node liveness value, and cIndex is this calculating gained liveness index in real time of reaching the standard grade of node, and hIndex went up line computation gained liveness index for node last time, and timeIndex is the time index of node, and speed is the speed index of node; Time index and speed index use formula (3), (4) and (5) to calculate respectively, wherein L is the duration of whole program, and t is the duration that program one is play, and S is the line duration of node, r is a video code rate, and Quantity is that node is always uploaded data volume during watching this program;
。
3. method as claimed in claim 2 is characterized in that the liveness result of calculation according to node, sets threshold values, node is divided three classes: high liveness node, middle liveness node and low liveness node; After with node-classification, the overlay network topology of an optimization of structure; Be about to the backbone network that high liveness node is constructed as whole overlay network, be responsible for the latest data that server produces is transported in each autonomy field system of whole overlay network apace and go; In a part of neighbor node of liveness node be high liveness node, obtain data and distribute from upper layer node at own place layer; The node that low liveness node is then selected a part of middle and high liveness is as neighbor node, and these nodes have mass data.
4. method as claimed in claim 3, it is characterized in that adopting following threshold values setting to carry out the division of level: aIndex greater than 1.2 the high liveness node that is, aIndex is middle liveness node between 0.8 to 1.2, and aIndex is less than 0.8 the low liveness node that is.
5. method as claimed in claim 3, it is characterized in that also adopting the asynchronous play strategy, the overlay network that is about to a channel is divided into several synchronous playing districts according to distance and network condition from data source according to autonomous territory, near from data source, play earlier in the zone that obtains data block earlier, from playing after a while of data source other node relay of needs far away; At identical or close playout-delay of having of same play area;
The playout-delay in autonomous territory is set the proportional playout-delay set algorithm that uses based on playout-delay, and the acquiescence playout-delay in promptly new autonomous territory calculates according to the playout-delay in the autonomous territory of contiguous more close data source; Because the playout-delay of a node is to be determined by its initial start skew and initial buffer time, in the P2P live broadcast system, the initial buffer time is fixed, as long as so calculate the initial start skew, the formula that following formula is offset for the silent initial start of calculating autonomous territory, wherein θ is the acquiescence initial start skew of node, f
p(t
0) be contiguous autonomous domain node P
nBroadcast point, α is system's adjustment factor, L
pBe P
nPlayout-delay,
6. method as claimed in claim 5, it is characterized in that the data buffer zone is divided into two sections according to functional requirement: forward direction buffering and back are to buffering, the forward direction buffering is used to store the data that are about to broadcast that other node sends, the back is used to store the data block of having play to buffering, and the data of back in buffering are the node services of those playout-delays greater than oneself.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105872058A (en) * | 2016-04-01 | 2016-08-17 | 太仓日森信息技术有限公司 | Mobile terminal live-broadcasting information pushing method and pushing device thereof |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20030120727A1 (en) * | 2001-12-12 | 2003-06-26 | Nikolai Mentchoukov | Method and system for file server direct connection |
| CN101924778A (en) * | 2009-06-10 | 2010-12-22 | 中国移动通信集团公司 | P2P (Point-to-Point) streaming media system, P2P user equipment and streaming media data transmitting method |
-
2011
- 2011-01-14 CN CN2011100074942A patent/CN102065149A/en active Pending
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20030120727A1 (en) * | 2001-12-12 | 2003-06-26 | Nikolai Mentchoukov | Method and system for file server direct connection |
| CN101924778A (en) * | 2009-06-10 | 2010-12-22 | 中国移动通信集团公司 | P2P (Point-to-Point) streaming media system, P2P user equipment and streaming media data transmitting method |
Non-Patent Citations (2)
| Title |
|---|
| DONGBO HUANG等: "Agiler: A P2P Live Streaming System with Low Playback Lag", 《COLLABORATIVE COMPUTING: NETWORKING, APPLICATIONS AND WORKSHARING (COLLABORATECOM), 2010 6TH INTERNATIONAL CONFERENCE ON IEEE》 * |
| DONGBO HUANG等: "Trading Bandwidth for Playback Lag: Can Active Peers Help?", 《MM "10 PROCEEDINGS OF THE INTERNATIONAL CONFERENCE ON MULTIMEDIA，ACM》 * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105872058A (en) * | 2016-04-01 | 2016-08-17 | 太仓日森信息技术有限公司 | Mobile terminal live-broadcasting information pushing method and pushing device thereof |
| CN105872058B (en) * | 2016-04-01 | 2019-03-19 | 贵州创鑫旅程网络技术有限公司 | A kind of method for pushing and its driving means of live broadcast of mobile terminal information |
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Application publication date: 20110518 |